Some arthropods, such as insects and arachnids (also called arachnoids), can be very serious pests. It is desired to control these pests. To that end many pesticides are known. However, most of those pesticides have an adverse effect on the environment. Also, some of those serious pests can develop an immunity to the pesticide. Such immunity can lead to the use of a stronger pesticide, which is even more harmful to the environment.
Quite a number of arthropods, especially those harmful to the human race, lay eggs in standing bodies of water. The eggs then hatch and form pupae or larvae. The pupae or larvae can be harmful in and of themselves. Adults of these species can also be harmful in and of themselves too, as well producing additional eggs, which lead to the harmful pupae or larvae.
For example, among the arthropods, mosquitoes are at best a nuisance and at worst a deadly threat to mankind. As a nuisance, a mosquito bite will itch, which can be especially annoying to a human. Such itching, can become infected by scratching. Such infections can become serious. Before that happens, it is usually desirable to treat the area of the bites with an over-the-counter treatment, or even a prescription medicine.
Beyond the nuisance factor, mosquitoes are carriers, or vectors, for some of humanity's most deadly illnesses, and they are public enemy number one in the fight against global infectious disease. Mosquito-borne diseases cause millions of deaths worldwide every year with a disproportionate effect on children and the elderly in developing countries.
Worldwide, malaria is a leading cause of premature mortality, in children under the age of five, with around 5.3 million deaths annually, according to the Center for Disease Control. Mosquitoes can carry the following diseases: yellow fever, dengue fever, epidemic polyarthrithis, rift valley fever, Ross River fever, West Nile Virus, chikunguya, eastern equine encephalitis, Japanese encephalitis, lacrosse encephalitis, saint louis encephalitis, western equine encephalitis, and tularemia. In addition, parasitic roundworm is spread by mosquitoes to dogs, cats, wolves, sea lions and even humans. Mosquitoes can also carry the filariasis worm, a parasite that causes a disfiguring condition (often referred to as elephantiasis) characterized by a great swelling of several parts of the body; leaving, worldwide, around 40 million people living with a filariasis disability.
Mosquitoes transmit disease in a variety of ways. In the case of malaria, parasites attach themselves to the gut of a female mosquito and enter a host as she feeds. In other cases, such as yellow fever and dengue, a virus enters the mosquito as it feeds on an infected human and is transmitted via the mosquito's saliva to a subsequent victim.
There are more than 3,000 species of mosquitoes, but the members of three bear primary responsibility for the spread of human diseases. Anopheles mosquitoes are the only species known to carry malaria. They also transmit filariasis (also called elephantiasis) and encephalitis. Culex mosquitoes carry encephalitis, filariasis, and the West Nile virus. And Aedes mosquitoes, of which the voracious Asian tiger is a member, carry yellow fever, dengue, and encephalitis.
Mosquitoes use exhaled carbon dioxide, body odors, temperature, and movement to hone in on their victims. Only female mosquitoes have the mouth parts necessary for sucking blood. When biting with their proboscis, they stab two tubes into the skin: one to inject an enzyme that inhibits blood clotting; the other to suck blood into their bodies. They use the blood not for their own nourishment but as a source of protein for their eggs. For food, both males and females eat nectar and other plant sugars.
The mosquito undergoes complete metamorphosis, going through four distinct stages in its life cycle: Egg, larva, pupa, and adult. The length of the first three stages is dependent on the species and water temperature. Culex tarsalis may complete its life cycle in 14 days at 20° C. (68° F.) and only ten days at 25° C. (77° F.). Some species have a life cycle of as little as four days, whereas in other species some adult females can live through the winter, laying their eggs in the spring. Many species of mosquito live their adult stage in roughly two weeks to two months.
All mosquitoes need water to breed, so eradication and population control efforts usually involve removal or treatment of standing water sources. Insecticide spraying to kill adult mosquitoes is also widespread. However, global efforts to stop the spread of mosquitoes are having little effect, and many scientists think global warming will likely increase their number and range.
Global warming, the progressive and gradual warming of the earth's surface temperature, is the most worrisome effect of climate change. Today, scientists and professionals in the medical field are particularly concerned with how climate change will affect the mosquito population and how it will subsequently give potential rises to a variety of dangerous infectious diseases. It is predicted that global warming will increase the risk of infectious diseases, and most particularly those that are prevalent in warm areas of the world. The spreading of disease will be facilitated by mosquitoes and other insects as warmer temperatures will allow them to propagate in areas further north. What this means is that diseases like malaria, dengue fever, yellow fever and encephalitis, which are common in warm weather countries, will begin to invade countries that previously had no reason to be concerned with such health problems.
To that end, it is very desirable to control the mosquito population and certain other members of the arthropod family. If such control may be achieved with no more than minimal effect on the environment, great advantages are obtained. If a device can effectively achieve the desired results, especially of mosquito abatement, without environmentally harmful pesticides, even greater advantages are obtained.